tanner



A. F. TANNER.

FILTER FOR CYANIDING SYSTEMS.

APPLICATION mu) FEB. 10. 1915.

1,317,835. Patented Oct. 7,1919.

4 SHEETS-SHEET I w/vwzsaza A. F. TANNER.

FILTER FOR cvAmnmc SYSTEMS.

APPLICATION FILED FEB- IO. I915.

Patented Oct. 7, 1919.

4 SHEETS-SHEET 2.

2 .IVIEN TM! v' fi. I

W/ r/vas Tm: COLUMBIA PMNneaAm A A. F. TANNER.

FILTER FOR CYANIDINGSYSTEMS.

APPLICATION FILED FEB. 10. l9l5.

1,317,835. Patented 0011. 7,1919.

4 HE'S-SHEET 4- W we fi W ,qrrm'msx I l mu m wunmru cm, WASIIINIIITON In c ALBERT F. TANNER, OF GREENIFIELLD, WISCONSIN,

CYANIDING PROCESS COMPANY, OF DAVENPORT,

ASSIGNOR TO IDEAL OON'I'INUOUS IOWA, A CORPORATION OF IOWA.

FILTER FOR CYANIIOING SYSTEMS.

Specification of Letters Patent.

Patented Oct. '7, 1919.

Application .filed February 10, 1915. Serial No. 7,383.

To all whom it may concern:

Beit known that I, ALBERT F. TANNER, a citizen of the United States, and resident of the town of Greenfield, in the county of Milwaukee and State of 'Wisconsin, have invented new and useful Improvements in Filters for Cyaniding Systems, of which the following is a descnption, reference being had to the accompanying drawings, which are a part of this specification.

This invention has for its object to provide a filter for straining clear cyanid solution from the slimes in a cyaniding plant,in order that said clear solution maybe suitably treated for recovering gold and silver, or other precious metal therefrom.

The invention is particularly designed as a part of the cyaniding system covered by my (id-pending a plication for Letters Patent Serial No. 8 8,998, filed December 26, 1914, wherein a continuous treatment of ore pulp is provided for Witha resulting eontinuous supply of spent cyanid solution requiring filtration on alarge, scale to separate the slirnies betoreftreatment for the recovery of the values contained, though it is not to be understood that the invention is confined in its use to such process, as it is suitable for use in any cyaniding process.

Another object of the invention is to provide a filter formed in sections capable of alternate use, and adapted for ready cleaning-of the filter surfaces.

1 Another object of the invention is to provide such a filter with an overflow compartment into which the solution and slimes will flow when the main filter surfaceshave become obstructed, and inl which filtration will take place as the liquids pass therev, v 'Another object of the invention is to pro vide' such overflow compartment 'with means for decantering clear solution therefrom,

-A11other object of the invention is to provide renewable filtering screens for draining the filter tank when the inai filter surfaces have become obstructed, and thereby enabling'the tank tobe emptied and cleaned.

Another object of the invention is to provide a sand filter with a sand bedcontained in removable baskets by means of which the r-aolution t'ron the filter tank may be further filtered by traveling upwardly theiethrough, suchhaskets containing filtering'sand being adnptedto be readily cleanedl 3 m' h w en ce 9 With the above and other objects in view the invention consists in the filter for cyanid- 'ing systems as herein claimed, and all equivalents.

Referring to the accompanying drawings, in which like characters of reference indicate the'same parts in the different views;

Figure 1 is a plan view of a filter for cyaniding systems constructed in: accordance with this invention;

Fig. 2 is a side elevation thereof;

Fig. 3 is a sectional plan iew through the filter screens of one of the duplicate sections of the filter tank;

Fig. 4 is a transverse sectional view therethrough on the plane of line -l:-l of Fig. 3;

Fig. 5 is a detail View of one of the re movable filter plates;

fFig. 6 is a transverse sectional view there- 0 Fi 7 is a detail view of one of the means for lifting the swinging filter screens with thegfilter screen in its lowered position;

Fig. 8 is a similar view thereof with the filter screen in its raised position;

Fig. 9 is a sectional plan view of one end of the sand filter and its connections With the filter tank- Fig. 10 is a longitudinal sectional view of this end of the sand filter;

Fig. 11 is a transverse sectional vien of the sand filter; and

Fig. 12 is a sectional view of the means for cleaning the sand baskets of the sand filter.

In tank-which is preferably e=evated on suitable supports and is provided with ani ine'lined bottom as shown. "The ,filter'ta-nk is preferably divided by a partitionl'? sons to constitute two separate filteringtank sections each having a sufficient capacity for twenty-four hours use, so that one tank sectionmay be available to receive thevalue bearing cyanid solution of the 'cyaniding plant, While the other is being drained and cleaned. The'two filter tank sections are identical in construction so that a detailed description of one Will serve for both' At the upper end'of the filter tank section'g'close these drawings 15 re resents, filter to the partitioiil'f, is a launder or delivery e tiankto delivrlthe value hearin'gfjcyanid solution 'tofthe filtertank' gust asitf the ova-hid ng 18 extending to near the b'dtiiomol t.

plant with the slimes and sand that are required to be removed before treatment to abstract the values held in the solution thereby.

At the outer lower corner of the filter tank section there is a rectangular depression 19 in the bottom of the tank covered by a false bottom of rectangular filter plates 20, consisting of perforated sheet metal lates covered with cocoa matting and filter abric. This false bottom is substantially flush with the main bottom of the filter tank and forms with the depression 19 a compartment for filtered solution, there being an alleyway 14 between the partition 17 and the said compartment for fi tering solution, along which the bottom of the tank is not depressed but remains the same as in the main portion of the tank.

Filter plates similar to filter plates 20 are arranged as fixed vertical partitions 21 and rest upon the false bottom. Other filter plates are pivotally mounted on vertical rods 22 to form swinging gates 23 extending obliquely across the filter compartments formed between the partitions 21, and the said rods 22 are located at the ends of the partitions 21 and are adapted to be raised or lowered to lift the filter gates 23 from contact with the false bottom when they are swung from one position to another and to lower them into contact with the false bottom in their operative positions. Each of the rods 22 is suitabl mounted so as to be capable of turning, t eir lower ends fitting in step bearings 24 provided with a spiral cam surface upon which bears a similar spiral cam surface of a collar 25 fixed on the rod, while the upper end of the rod, as seen in Fig. 4, is rovided with flat faces 26 to form a wrenc hold adapting it for engagement by a wrench or crank for turning it and thereby causing the cam surfaces of the bearing 24 and collar 25 to raise or lower the rod and thereby raise or lower the filter gates 23, for the hinges of the latter rest on pins 27 projecting from the rod 2-2.

The arran ement of the partitions 21 and the hinged filter gates 23 is such that a con tinuous zi -zag filter wall is roduce-d of oonsiderab e area and of a heig t somewhat less than the height of the walls of the filter tank, so that as the level of the liquid in the filter tank rises it will overflow into the filter chamber 27 behind the filter wall. Although the first filter gate 23 does not reach to the side wall of the filter tank, nor does the last filter ate 23 fit against the end of the filter tank, tfie filter chamber is nevertheless closed from communication with the main portion of the filter tank because of the presence of an imperforate wall 28 in the former location and a filter drain box 29 in the latter location. The wall 28 is in the form of a short partition corresponding with the partitions formed by the perforated filter plates 21 and engaged by the end of the first filter ate 23 in the same manner, leaving said fi ter gate free to swing away therefrom to a position against the first filter partition 21, when it is desired to clean the filter surfaces, the other filter gates being capable of being swung back in a like manner at such times to render all of the filter surface accessible for cleaning.

The false bottom terminates a short distance from the end wall of the filter tank, though the depressed portion of the bottom of the filter tank continues to the end, and end and side walls 30 convert this uncovered portion of the depressed bottom into a trough-like gutter 31 into which the filter drain box 29 discharges. The side and end walls 30 of the gutter 31 only extend u to the level of the false bottom of the lter compartment of which it forms a part. A decanter drain pipe formed of sectionspivotally connected together and passing through the bottom of the gutter 31 is adapted to be raised or lowered to have its open end positioned at any desired elevation from a position within the gutter and beneath the level of the false bottom to a position near the level of the upper edges of the filter plates forming the walls of the filter chamber. This decanter drain pipe is for the purpose of draining the partially clear solution from near the surface of the solution in the filter chamber after there has been an overflow of solution into the filter chamber as the result of the filter plates becoming clogged. The solution which overflows the filter lates is comparatively clear solution from t e fact that it is taken from the top of the large body of solution contained in the main portion of the tank from which the slimes have had an opportunity to settle, and by decantering the solution from the top of the body of solution in the filter chamber, after giving opportunity for settlement of such shmes as may have been carried over therewith, thesolution drawn off by the decanter pipe may be quite as free from slimes and sand, as that solution which has filtered through the filter plates into the filtered solution compartment beneath the false bottom.

In order that the body of solution contained in the main portion of the filter tank may be filtered as it is drained for emptying the tank, the filter drain box 29 is provided, which is best seen in Figs. 3 and 4, and consists of vertical side walls provided with a series of guide flan cs 33 and a bottom wall, preferably covere with filter fabric, the guide flanges 33 being adapted to receive between them removable filter slides 55% which, as shown in Figs. 5 and 6, consist of perforated sheet metal plates covered with cocoa matting and filter cloth. During the llie f e e ete e ew et e eeltee lelivdes 4mm t z i'n h fil e dremhee e ween fir teee Qt eeg e fiee eee mee e @118? nay tthe'me eip et ei Q i t e ea ed; eflbefiee el e e 4 150 he 1 t nt n ed we ie e filter. tank isrdre negh T e utien thr e A ithth tslime eve e e lt e fieeerhe meeetwhen by the decanter p e i i pipeafie e e i eez he wk rt em Q laereeeelet m e m et ee e .e 1 i chexgee hre eh e I f .1 pemfie-a seee mfieie -i 1 fore reaching t e valve h figlldi mu hii zlalt r n h lin d etmm, n s.- neef ehlv e ee ioned engs ee fi ee e 2 and munte i on the esuppegtegtheg'ew raok;.38 extends 0W1, theentme open JIPPBI' part of: the. trough, exeegt at the deeRer. end of the trough wherefiheplipe; entere, and here h ough i P ZQHQQQME PH': e ,19- Werdly ylteede ngepemei ea fi eelthmew selnta u im yi use e0 h eher; lene 'th the s me eieth egh pmperzsnme 1e esfi 1811; Represent-e heed sefliment toteireei the solution thmug'h the send fil ere-end over t rear dge efi-the; trough wh eh is slight y we than-the, frontedge a i seen an Eig, 11. The. rack 3HJI'QHW5 a. support iona seeiee of sheet metal baskets; .40 which are; seated: on packing-'jstripsil QfPfBIh-Or other; eultebl fiaekingfmaterifll Withwhieh is covered, such tight? of theifikter ibaslietsf on the suppbmingeflicle fiseeenviegete pnevent the1eo'lufimep eeeeumiehfheakegmid equ ing tt eriee hxtpegh t ei ier Qf the baskets whi o'li 7 ag pa tially; ed with sand and ha e 'ierfgme (hot-t9; ecoyered with owemet eee di 1 5m lqe e besketg fit, enoeshers ggwhl eh eone piet bf e ou h, and 1 St ye 9: p ev i fii l ee ep z ed ne m like meenpeeeeeee geeqhht keyfpree e1; HP werlne te it Jig-4 H 1 be 1$ the lower rear egg gigthe r he et eep tm te n ee ti d gutter Mew 'iehfeeri ies it away for Subsequent treatmen to #19 316? he l e h re rom- Inaemuch all, of; the solution passing through h filter. be keteisicohduqted over the edge of the tlzough by means of the lips 43, the presenee of liquid ound the beskets would mdieete an improper seeting of one 0i theibasketsso that theeolutionrmay be tem t e eeeeheefi iee w Pe ne e te m tee; eleeae e eh n e 1 uiet 1 h t lieli wrin :0 ra i e. m1 e feet cel With an imp-er eetl seetei basket the pressure o f the heed o diquid in the w 39 w d be nefi eiive fe f c the solution th -oughrthe resjst-anee 0f the lter bed as the: spec e'betgvqeen the improiyer'lyVseeted'haLsket -end its support wou d offer less :reei stenee tofthe How of solution and thev slimes wouhl he carried through th ltewith endapyer the edge o the trough, and the'filteriwouid not beproperly done. The weight 0 the'fiieen baskete and their eoutentseerves t'o held them firmly seated on the packing strips 4110f the supporting shoulders and. theeross ribs and the presence of sand or any ether material holding the besketslout Ofeee Iinge nnectiQn willbe indicated by the rising solution between the baskets, Each oitheeand filter baskets 41) is provided iwitht'eliding bail handles 45 by: m me at which 155 may-be; lifted when it, is'desiredjo cleenith fi ter material, which is donej by merelyrplaoingthehbesket in a holder 46 in which the basket exagctly fits,

- and thenradmitting. yveterthtough a valved pipe 47 to 'the'bottom of the holder so that the water flows upwardly throughthe basket with force, lifting the send; therewith and agitating it while flushing the slime and rry ng t flfeie theioverfl ew around the uppeee ges f; he holder 7 Inorderftha the mnghfiiemeyjhellreined lBO and in order to seal the joints between meeting edges they are shown as having eirtending flaps held in place by metalrods 51 resting thereon, and the filter plates 20 which form the false bottom are removable for cleanin thedepressed bottom "rtion 19 of the tan which is rovided wit 1 a clearl -out opening 52 at its owered portionito facili tate such operation, the gutter 31 having a similar clean-out opening 53.

The operation of thefilter has been described incidental to the description of the construction thereof, but briefly reviewed I is as follows: The solution from the cyanidin'g plant is admitted through the launder 18 to the upper end of the tank 15 near the inclined bottom and flows to the filter chamber at the lower endof the tankwhere it percolates through such portions of the filter covered. false bottom .as are exposed outside of the zi zagwall f the filter chamber, the clear, fiitered soiution passing into the depressed filter compartment beneath the false bottom and out through pipe 35 and open valve 36 to'the sand filter trough 37 which is soon filled, and owing to the siight resistance ofl'ered by the sand fitter baskets to the passage of the solution therethrough a liquid level will be established in the open trunk portion 39 of the trough slightly higher than the overflow lips 43of the filter baskets. The pressure due to th s head will cause the liquid to force its way slowly through the sand filterbed formed by the numerous sand baskets on the same ievel, and overflow over the lips 43 inte'the inclined gutter 44 by which it is carried 01f to be treated forthe recoveryof values therefrom. As the filter surface outside 'ofjthe filter chamber becomes clogged bythedeposit of slime thereon the level of the solution' in the filter tank will rise, bringing more and more of the filter surface of the walls of said filter chamber into action, the clear solution passing through saidwalls into the filter chamber and tiienthrou-gh the filter surface in the bottom of the fiiter chamber tothe' filter compartment beneath, and on through the sand filter as before. Eventually the depth of solution in" the tank 15 becomes so great as to overflow the walls of the filter chamber owing to the clogging of the filter surface of said walls, but by this time the surface of the body of solution in. the filter tank is comparatively clear owing to gravity separation of the slimes and sand, and sucirsolution as overflows passes through thefaise bottom inte thefiltered solution compartment beneath and then through the sand filter. When the filter chamber becomes filled with solution and slime at the end of the twenty-four hour period the supply of solutionto the tank is discontinued and shifted to the other tank where the process is repeated. Immediately,

the filter slide that has been .in position 'up to this time, the latteribeing then removed and-permitting the solution within the tank to percolatethrou h the filter surface of the clean filter slide, t e filtered,solution flowing out through the decanter pipe tothe sand filter; Other filter slides are substituted in succession'until the tank is emptied of soluti'onan'd oor'ltainsonly the shrines and sand; The value then closed and the tank is cleaned' 'by scraping the .slimes and sand from f the I walls thereof, and from all filter surfaces, and washing' the latter with a hose, therebeing' a clean-out opening '49 in the bottom ofthe'tankat the'lowestend of the alleyway through which the refuse, matter is discharged. In order to facilitate the cleanin of the filter surfaces the filter gates 23 are rst elevated by turning the rods 22 as described, and are then swung back against the filter partitions21, thus rendering the entire. false bottom available for cleaning, as well as the filter partitions 21, and the filter gates 23 which may have their filter surfaces scraped and scrubbeii' and flushed witha stream ofwater from a hose.

The parts are then rammed to their original positions and the filter section is again ready to'receive a fresh supply'of solution to relieve the other filter tank at the end of its period of operation.

The sandfilters may be'cleaned during the period of inactivity draining 'the'solution' from thetroughhymeans of the decanter 'ip'e 48, and'then placing each sand basket 11 the cleaner 46 and forcing a stream of water therethrough, as described, the sedimentin *the bottom of the trough 37 be ing removed through a clean-out pipe 50 in the bottom of the'lower end thereof.

: By 'nieans'of the filter of'this invention a large quantity of Value bearing solution, as produced wish s. oontinuouscyaniding process, such as that describedin 'my' (:0- pending application referred to, may be thoroughiy and efiectively separated from the accompanying-sand and slimes which would'intenferewiththe action of the precipitationrcr recovering the valuestherefrom, and the supply'of clean solution is maintained practically continuously because of the"arrangement' of' filter surfaces, enabling-one'filter surface after another to be brought into action as the obstruction of filterlng surfaces progresses and enabling the Withdrawal of all of the cyanid solution so that practically no values are lost.

What I claim as new and desire to secure by Letters Patent is:

1. In a filter, a trough having an inclined bottom and an upwardly extending trunk projection at its end, means for supplying the trough with liquid, a rack within the trough, filter baskets fitting within the trough upon the rack and having a sealin connection therewith to seal the opening 0 the trough, a filter plate in the bottom of each of the filter baskets supporting sand within the filter basket to form a filter bed, lips projecting from the edges of the filter baskets over the edge of the trough, a gutter beneath the lips to catch the liquid falling therefrom, and a 'ointed decanter pipe at the lower end of t e trough adapted to be moved into the trunk extension of the trough for draining the liquid from the trough.

2. In a, filter, a trough having means for en l in ii uid thereto, supporting shouldei si logg tie side and end walls of the trough and spaced from the edges thereof, ribs extending across the trough, rectangular sand baskets seated on the supporting shoulders and the ribs, the adjacent baskets seated on the same rib whereby the o ening of the trough is completely sealed y the sand baskets and the sand baskets are held in their sealing relation by means of their weight, and the weight of their contents, one edge of each basket being lower than the others and bent outwardly to form a 1i extending over the edge of the troug whereby the liquid in the baskets is caused to rise higher than the edge of the trough and be conducted out of the trough without filling the space between the baskets.

In testimony whereof I afiix my signature in presence of two witnesses.

ALBERT F. TANNER.

Vitnesses:

R. S. C. CALDWELL, KATHERINE HOLT,

copies of this patent may be obtained for five cents each, by addressing the Gommissioner of latents, Washington, D. O. 

